1. Field of the Invention
The present invention relates to an image forming apparatus with an attachment such as a sorter, and more particularly to such an image forming apparatus with attachment capable of displaying that the desired number of image processings exceeds the processing capacity of said attachment to be used in combination with said image forming apparatus.
2. Description of the Prior Art
The use of an attachment such as a sorter in combination with an image forming apparatus for improving the work efficiency of the apparatus such as a copier or a printer is already known. However, when processing a number of copies exceeding the processing capacity of said attachment is instructed, the copies exceeding said processing capacity are processed as if said attachment does not exist, so that the attachment does not contribute to the improvement of work efficiency in such case.
For example, in a usual combination of a copier and a sorter, the copier is capable of producing copies up to the maximum set number, while the sorter sequentially sorts the entered copies and puts all the copies exceeding the sorting capacity into a particular non-sort bin. If 40 copies are introduced into a sorter having 20 sorting bins, the first 20 copies are thus sorted but the remaining 20 copies exceeding the sorting capacity are put into the non-sort bin. In case of sorting 40 sets of copies each consisting of 30 pages with such sorter, the first 20 sets can be sorted by distributing copies into 20 bins 30 times, but the copies put into said non-sort bin amount to 20.times.30=600 copies, which have to be manually sorted with a significant cost in time and labor.